R = float(input())

if R >= 30:
    print("Yes")
else:
    print("No") R = float(input()) R float(input()) float input() input if R >= 30:
    print("Yes")
else:
    print("No") R >= 30 R 30 print("Yes") print "Yes" print("No") print "No" R = float(input()) float(input()) R
R = float(input())

if R >= 30:
    print("Yes")
else:
    print("No")